1. Academic Validation
  2. Cholesterol esterase accelerates intestinal cholesterol absorption

Cholesterol esterase accelerates intestinal cholesterol absorption

  • Biochim Biophys Acta. 2002 May 10;1571(1):34-44. doi: 10.1016/s0304-4165(02)00204-0.
Ikuo Ikeda 1 Ryosuke Matsuoka Tadateru Hamada Kosuke Mitsui Sachiko Imabayashi Akira Uchino Masao Sato Eiichi Kuwano Tomoaki Itamura Koji Yamada Kazunari Tanaka Katsumi Imaizumi
Affiliations

Affiliation

  • 1 Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan. iikeda@agr.kyushu-u.ac.jp
Abstract

Mechanisms of acceleration of Cholesterol absorption by Cholesterol esterase were investigated in various experimental conditions. Lymphatic recovery of Cholesterol intubated as a micellar solution containing phosphatidylcholine (PC) into the duodenum was enhanced by the co-administration of Cholesterol esterase in rats drained of bile and pancreatic juice. However, no accelerated incorporation was observed when Cholesterol was solubilized in PC-depleted micelles. Cholesterol esterase dose-dependently accelerated the incorporation of Cholesterol into differentiated Caco-2 cells, only when Cholesterol was solubilized in PC-containing micelles. The accelerated incorporation of Cholesterol into Caco-2 cells by Cholesterol esterase disappeared when the Enzyme was preincubated with a suicide inhibitor of Cholesterol esterase. Cholesterol esterase has an activity as Phospholipase A(2). When 10% of PC in bile salt micelles was replaced by lysophosphatidylcholine (lysoPC), the incorporation of Cholesterol into Caco-2 cells was significantly accelerated. Cholesterol esterase enhanced the incorporation of micellar Cholesterol into brush border membranes prepared from the rat jejunum. The addition of Cholesterol esterase to bile salt micelles accelerated the release of micellar Cholesterol in a dose-dependent manner, only when the micelles contained PC. These observations strongly suggest that Cholesterol esterase hydrolyzes PC in bile salt micelles and thereby, accelerating the release of Cholesterol from bile salt micelles. This may be a major cause of the acceleration of Cholesterol absorption by Cholesterol esterase.

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